# PX4 SD Card Layout

The PX4 SD Card is used for storing configuration files, flight logs, mission information etc.

:::tip
The SD card should be FAT32 formatted for use with PX4 (this is the default for SD cards).
We recommend that you reformat cards that are using a different file system.
:::

The directory structure/layout is shown below.

| Directory/File(s)             | Description                                                                                                                   |
| ----------------------------- | ----------------------------------------------------------------------------------------------------------------------------- |
| `/etc/`                       | Extra config. See [System Startup > Replacing the System Startup](../concept/system_startup.md#replacing-the-system-startup). |
| `/log/`                       | Full [flight logs](../dev_log/logging.md)                                                                                     |
| `/mission_log/`               | Reduced flight logs                                                                                                           |
| `/fw/`                        | [DroneCAN](../dronecan/README.md) firmware                                                                                    |
| `/uavcan.db/`                 | DroneCAN DNA server DB + logs                                                                                                 |
| `/params`                     | Parameters (if not in FRAM/FLASH)                                                                                             |
| `/dataman`                    | Mission storage file                                                                                                          |
| `/fault_<datetime>.txt` | Hardfault files                                                                                                               |
| `/bootlog.txt`                | Boot log file                                                                                                                 |
